Such a device is disclosed in WO, A2, 03/015424 and results in a display that is switchable between a 2D mode and a 3D mode. A rotator layer may be used to adapt commercially available controllable LC layers, which are often oriented at 45° and 135° azimutal angle to the main direction of the lens layer which is vertical (azimutal angle 90+/−10°) as seen from a user.
A problem with such a display is that the contrast ratio in either the 2D mode or the 3D mode is insufficient for many applications.